An actuator of this type is generally known and is used, for example, to interrupt electrical connections or to trigger fast switching procedures, e.g. in the motor vehicle safety sector.
The pyrotechnic pressure element, which is also called a pyrotechnic igniter in the case of an electrical activation, has the advantage in addition to a particularly fast power development that the energy required to move the actuator element can be stored without pressure over a long period of time by means of suitable chemical substances and can be released as required by means of a comparatively small electrical or mechanical energy.
An activation of the pressure element triggers a conversion of the chemical substances and results in the generation of a pressure impulse by which the actuator element is moved relative to the actuator housing, e.g. is pushed out of it. Since the action on the actuator element takes place very abruptly, the actuator element is moved in a short time and in an uncontrolled manner from a starting position into an end position.
This fast and uncontrolled movement of the actuator element has proved to be disadvantageous in those applications in which the movement procedure of the actuator element should endure for a specific time and/or a bounce of the actuator element should be avoided, e.g. in locking or unlocking processes.
It is the underlying object of the invention to provide a pyrotechnic actuator, wherein the movement of the actuator takes place in a controlled manner.
An actuator having the features of claim 1 is provided to satisfy this object.
The actuator in accordance with the invention comprises an actuator element movably stored at an actuator housing, a pyrotechnic pressure element for the movement of the actuator element and a control means for the control of a force exerted onto the actuator element by the pressure element to move the actuator element.
The force exerted on the actuator element on a triggering of the pressure element can be set by the control means such that the movement of the actuator element takes place at a desired speed. The control means is in particular adjustable such that the movement of the actuator element takes place over a desired period and/or a bounce of the actuator element is avoided. A defined movement of the actuator element can therefore be pre-set by the control means and a matching of the actuator to its respective area of use is possible.
Advantageous embodiments of the invention can be seen from the dependent claims, from the description and from the drawing.